1. Field of the Invention
This invention relates to latch assemblies as used on repositionable elements, such as closure elements, and, more particularly, to a latch assembly having a catch assembly which is releasably engageable with a strike element to maintain the closure element in at least one predetermined position relative to a support for the closure element.
2. Background Art
Latch assemblies are utilized in myriad different environments for both static and dynamic applications. In one exemplary latch assembly, a catch assembly is provided within a component space defined by a housing. The catch assembly has at least first and second different states. The catch assembly includes a rotor that is in a first, primary latched position with the catch assembly in the first state and a second position with the catch assembly in the second state. In the first position, the rotor engages a strike element so as to prevent separation of the strike element from the latch assembly. With the rotor in the second position, the strike element, which is held by the latch assembly with the rotor in the first position, is permitted to be separated from the latch assembly. The rotor commonly has a third, secondary latched position, between the first and second rotor positions. With the rotor in the third position, the latch assembly is in a third state, wherein the rotor engages the strike element to prevent separation of the strike element from the latch assembly.
The rotor has a U-shaped opening to receive the strike element. With the rotor in the first position, and the strike element within the rotor opening, escape of the strike element is prohibited by a strike surface on a strike plate which blocks the rotor opening by bridging two spaced legs between which the strike element moves. With the strike element engaged by the latch assembly, and a closure element with which the latch assembly is associated in a first position, attempted movement of the closure element from the first position into a second position therefor causes a force to be imparted by the strike element through the rotor and strike plate to the housing. It is important that the housing does not respond to this force by bending/deflecting to the point that the strike element might escape from between the rotor and strike plate. In certain applications, such as on moving vehicle doors, the forces tending to compromise the connection of the latch assembly and strike element may be substantial. Aside from the fact that the magnitude of these forces may be quite large, governmental regulations often impose stringent requirements on the ability of these latch assemblies to resist forces even greater than those typically encountered.
Conventionally, the relationship between a strike element and rotor, with the rotor in the first position therefor, is characterized as being either “in pocket” or “out of pocket”. The in pocket relationship occurs with the captive strike element bearing against one arm on the rotor and remaining spaced from the strike surface on the strike plate. That is, the strike element penetrates the U-shaped opening sufficiently that with the rotor in the first position therefor, the strike element remains spaced from the strike surface on the strike plate. As the force generated on the first arm by the strike element increases, as in the event that the closure element is urged forcibly from the first position towards the second position therefor, a deflection/bending of the housing may occur to the point that the strike element bears simultaneously against the first arm of the rotor and the strike surface on the strike plate. This results in the strike element being out of pocket. For a typical construction, the ability of the latch assembly to withstand additional loading is greater with the strike element in the in pocket state then in the out of pocket state. Thus, ideally, the latch assembly design takes into consideration the maintenance of the in pocket state to the highest loading anticipated. This objective, however, may compete with that of rigidifying the housing without increasing its perimeter dimensions. The industry continues to seek out designs which improve overall strength without dimensional variations for the housing.